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1.
Front Biosci (Elite Ed) ; 16(2): 16, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38939913

RESUMEN

BACKGROUND: This study investigated the ultraviolet (UV) absorption spectra of various types and ages of grape wines and the correlation these spectra presented with their phenolic constituents. Firstly, the differences in UV spectra were characterized for different wine samples, depending on their type and age. METHODS: The following methods were used in this study: ultraviolet visible spectrophotometry, Folin-Ciocalteu spectrophotometric method, high-performance liquid chromatography. RESULTS: Then, it was demonstrated that for identically aged wines, the 280 nm absorbance is proportional to the concentration of phenolic compounds, as determined by the Folin-Ciocalteu method. Next, an investigation was conducted into the absorption coefficients of different phenolic classes commonly found in grapes and wine. Finally, the range in variation of phenolic compounds in various types of grape wines was established. CONCLUSIONS: This work provides a methodological approach to rapidly determine the concentration of phenolic compounds in wines using UV spectroscopy, provided that their age is known. As UV spectrophotometers are available in nearly all laboratories, this may provide a cheaper and faster alternative to current methods, including high-performance liquid chromatography (HPLC).


Asunto(s)
Fenoles , Espectrofotometría Ultravioleta , Vino , Vino/análisis , Fenoles/análisis , Fenoles/química , Cromatografía Líquida de Alta Presión/métodos
2.
Nat Prod Res ; : 1-8, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38598360

RESUMEN

This study aimed to evaluate the antioxidant potential of autochthonous Hydnum repandum through LC-MS/MS profiling, total phenolic content (TP), total protein content (TPR), and antioxidant capabilities (DPPH, ABTS, and FRAP assays) across various extracts (CHCl3, acetone, 70% EtOH, 80% MeOH, and hot water). LC-MS/MS analysis revealed a predominant presence of quinic acid in polar solvents (ranging from 531.37 to 676.07 ng/mL), while EtOH and MeOH extracts exhibited elevated total phenolic levels (27.44 ± 0.32 and 28.29 ± 3.62 mg GAE/g d.w., respectively). Impressively, H. repandum showcased remarkable antioxidant properties, as evidenced by its FRAP values (57.29 to 199.96 mg AAE/g d.w.), ABTS values (5.69 to 29.95 mg TE/g d.w.), and IC50 values in the DPPH assay (91.40 to 372.55 µg/mL), which exhibited a strong correlation with TP. Notably, the acetone extract exhibited the most robust antioxidant activity where the highest TPR was observed, suggesting synergism of primary and secondary metabolites.

3.
Int J Mol Sci ; 24(14)2023 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-37511004

RESUMEN

In this study, growth parameters of underground parts and concentrations of phenylpropanoids, phenylethanoids, flavonoids, hydroxybenzoic acids, and catechins in aqueous-ethanol extracts of 6-year-old cultivated plants of Rhodiola rosea (propagated in vitro) of Altai Mountain origin were analyzed, and differences in chemical composition among plant specimens and between plant parts (rhizome and root) were evaluated. High-performance liquid chromatography detected 13 phenolic compounds. Roots contained 1.28 times higher phenylethanoids levels (1273.72 mg/100 g) than rhizomes did. Overall, the concentration of phenylethanoids in underground organs was not high and ranged from 21.36 to 103.00 mg/100 g. High variation among R. rosea individual plants was noted both in growth characteristics and in levels of secondary metabolites under our cultivation conditions. It was found that concentrations of phenylpropanoids, phenylethanoids, and catechins significantly depend on the plant part analyzed (p ≤ 0.05). Specimen No. 4 is characterized by the highest concentration of rosavins (1230.99 mg/plant) and the lowest concentration of cinnamyl alcohol (62.87 mg/plant). Despite the wide range of values, all 10 tested specimens (underground part) met the minimum requirements of the United States Pharmacopeia (2015) for rosavins (0.3%) and of the Russia State Pharmacopoeia (2015) for the average level of rosavins (roots): (1%).


Asunto(s)
Catequina , Rhodiola , Raíces de Plantas/química , Extractos Vegetales/química , Rhodiola/química , Siberia , Individualidad
4.
Foods ; 12(12)2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37372638

RESUMEN

Hawthorn (Crataegus monogyna Jacq.) and whitebeam (Sorbus aria (L.) Crantz) are wild species traditionally used as ethnic foods in the Mediterranean area. Their red berries, and mainly the peels, may be used as ingredients due to their color (replacing other synthetic colorants) or functional properties. Some previous studies analyze all edible fruits, but there is very little literature on the composition and properties of the pulpless epidermis of the fruits of C. monogyna and no literature concerning the fruits of S. aria. Total phenolic compounds (TPC) and families of hydroxybenzoic acids, hydroxycinnamic acids, flavonols, and total monomeric anthocyanins were determined in the epidermis of C. monogyna and S. aria fruits. The in vitro antioxidant capacity was also determined using QUENCHER (Quick-Easy-New-CHEap-Reproducible) methodology. Anthocyanins profiles were analyzed in hydroalcoholic extracts through HPLC/MS. C. monogyna fruits presented higher content of TPC than S. aria, with hydroxybenzoic acids (2870.6 mg GAE/100g dw) as the major family, followed by flavonols (771.4 mg QE/100 g dw) and hydroxycinnamic acids (610.3 FAE/100 g dw). Anthocyanins were found in 251.7 mg cyanidin-3-glucoside/100 g dw, characterized by the content of cyanidin-O-hexoxide and peonidin-O-hexoxide. The levels of these compounds correlated with higher values of a* parameter (higher intensity of reddish color). These fruits also showed higher antioxidant capacity by Q-Folin-Ciocalteu and Q-FRAP. S. aria peels had fewer phenolic compounds, particularly anthocyanins (33.7 mg cyanidin-3-glucoside/100 g dw), containing different cyanidin derivatives. From these results, new insights about the composition of the epidermis of these wild fruits are provided, and their potential as ingredients for the food industry is corroborated.

5.
Molecules ; 28(11)2023 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-37298872

RESUMEN

Acacia saligna is native to Western Australia. It has become an introduced and fast-growing plant in other parts of the world due to its ability to adapt to drought, saline and alkaline soils, and hast growing environments. Studies on the bioactivities and phytochemicals of the plant extracts were conducted. However, comprehensive information that links those bioactivities to the identified compounds in the plant's extracts is still lacking. Data gathered in this review revealed a rich chemical diversity of hydroxybenzoic acids, cinnamic acids, flavonoids, saponins, and pinitols in A. saligna growing in Egypt, Saudi Arabia, Tunisia, South Africa, and Australia. The variability in phytochemical composition and quantity could be attributed to plant parts, growing locations, extraction solvents, and analysis methods. Identified phytochemicals support observed biological activities such as antioxidant, antimicrobial, anticancer, α-glucosidase inhibition, and anti-inflammation in the extracts. The knowledge of chemical structures, biological activities, and possible mechanisms of action of the bioactive phytochemicals identified in A. saligna were discussed. In addition, the structure-activity relationships of dominant active compounds were examined to explain the bioactivities exerted by A. saligna extracts. The review provides valuable insights towards future research and the development of new therapeutics from this plant.


Asunto(s)
Acacia , Antiinfecciosos , Acacia/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Fitoquímicos/farmacología , Fitoquímicos/análisis , Antiinfecciosos/farmacología , Antioxidantes/química
6.
J Am Nutr Assoc ; 42(1): 15-26, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-34648393

RESUMEN

Objective:Epidemiological studies have shown associations between polyphenol consumption and reduced risk of cardiovascular diseases. This study aimed to assess the association between polyphenol intake and the prevalence of hypertension.Methods:This cross-sectional study was performed on data from the Cohort of Universities of Minas Gerais (CUME) project. Participants completed an online food frequency questionnaire, and polyphenol intake was assessed using the Phenol-Explorer database and articles. Hypertension was determined by a medical diagnosis, having a blood pressure ≥ 130 mmHg/80 mmHg, or using antihypertensive drugs. Adjusted logistic regression models were used to estimate the odds ratios (ORs) and 95% confidence intervals (95% CIs) for the prevalence of hypertension.Results:The prevalence of hypertension was 39.57%, and the average intake of total polyphenols was 860.79 mg/day. The highest (5th quintile) intake of flavonoids (mean: 368.46mg/day; OR: 0.83; 95%CI 0.70; 0.97), hydroxybenzoic acids (mean: 379.38mg/day; OR: 0.77; 95%CI: 0.66;0.91), and flavonols (mean: 44.13mg/day; OR: 0.79; 95%CI: 0.67; 0.93) was inversely associated with hypertension prevalence, compared to the lowest intake (1st quintile).Conclusions:Our findings demonstrate that the intake of flavonoids, hydroxybenzoic acids, and flavonols is associated with a lower prevalence of hypertension.


Asunto(s)
Hipertensión , Polifenoles , Humanos , Prevalencia , Estudios Transversales , Hipertensión/epidemiología , Flavonoides , Hidroxibenzoatos , Flavonoles
7.
Int J Mol Sci ; 23(15)2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35955684

RESUMEN

Pharmaceutical cocrystals can offer another advanced strategy for drug preparation and development and can facilitate improvements to the physicochemical properties of active pharmaceutical ingredients (APIs) without altering their chemical structures and corresponding pharmacological activities. Therefore, cocrystals show a great deal of potential in the development and research of drugs. In this work, pharmaceutical cocrystals of ethenzamide (ETZ) with 2,6-dihydroxybenzoic acid (26DHBA), 2,4-dihydroxybenzoic acid (24DHBA) and gallic acid (GA) were synthesized by the solvent evaporation method. In order to gain a deeper understanding of the structural changes after ETZ cocrystallization, terahertz time domain spectroscopy (THz-TDS) and Raman spectroscopy were used to characterize the single starting samples, corresponding physical mixtures and the cocrystals. In addition, the possible molecular structures of ETZ-GA, ETZ-26DHBA and ETZ-24DHBA cocrystals were optimized by density functional theory (DFT). The results of THz and Raman spectra with the DFT simulations for the three cocrystals revealed that the ETZ-GA cocrystal formed an O-H∙∙∙O hydrogen bond between the -OH of GA and oxygen of the amide group of the ETZ molecule, and it was also found that ETZ formed a dimer through a supramolecular amide-amide homosynthon; meanwhile, the ETZ-26DHBA cocrystal was formed by a powerful supramolecular acid-amide heterosynthon, and the ETZ-24DHBA cocrystal formed the O-H∙∙∙O hydrogen bond between the 4-hydroxy group of 24DHBA and oxygen of the amide group of the ETZ molecule. It could be seen that in the molecular structure analysis of the three cocrystals, the position and number of hydroxyl groups in the coformers play an essential role in guiding the formation of specific supramolecular synthons.


Asunto(s)
Amidas , Oxígeno , Cristalización , Teoría Funcional de la Densidad , Estructura Molecular , Preparaciones Farmacéuticas , Salicilamidas
8.
J Food Sci Technol ; 59(11): 4553-4562, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35789584

RESUMEN

The well-known health beneficial properties of beer are mainly due to phenolic antioxidants. Citrus-flavored beers represent a growing side-market in the beer industry, sparingly investigated to date. The phenolic profile of commercial radler beers (R1, R2) was investigated to evaluate the impact of the lemon juice added to beer in the industrial production. Results were compared to those obtained for opportunely chosen commercial beer (B) and lemonade (L). The study was carried out by an HPLC-MS/MS with an electrospray ionization source in selected ion recording mode, analyzing in a single chromatographic run 26 compounds belonging to the different phenolic classes of hydroxybenzoic, hydroxycinnamic and caffeoylquinic acids, flavonoids and prenylflavonoids. Different phenolic profiles were found for R1 and R2, mainly ascribed to different malt/hop/recipe used for the beer. High to very high level of hesperidin were found in the radlers, so that a major impact on phenolic antioxidants of the radlers was due to the lemon. Similarly, a major impact of the lemon aromas was found, D-limonene being the dominant peak resulting from the GC-MS analysis of the volatile fraction of the radlers.

9.
Nutrients ; 14(12)2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35745206

RESUMEN

One of the symptoms of Alzheimer's disease (AD) is low acetylcholine level due to high acetylcholinesterase (AChE) activity. For this reason, AChE inhibitors are used in the treatment of AD, the prolonged use of which may cause a cholinergic crisis. There is a need to search for safe natural AChE inhibitors. The study analyzed 16 hydroxybenzoic acids using calorimetry and docking simulation as AChE inhibitors. All tested compounds were shown to inhibit the hydrolysis of ACh. The best properties were shown by methyl syringinate, which acted as competitive inhibitor at a catalytic site. The tested compounds also interacted with the anionic or peripheral binding site known to block ß-amyloid plaques formation. The activity of the tested hydroxybenzoic acids IC50 ranged from 5.50 to 34.19 µmol/µmol of AChE, and the binding constant Ka from 20.53 to 253.16 L/mol, which proves their reversible, non-toxic effect, and activity at physiological concentrations.


Asunto(s)
Enfermedad de Alzheimer , Inhibidores de la Colinesterasa , Acetilcolina/metabolismo , Acetilcolinesterasa/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , Calorimetría , Inhibidores de la Colinesterasa/química , Humanos , Hidroxibenzoatos , Simulación del Acoplamiento Molecular
10.
Sensors (Basel) ; 22(4)2022 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-35214507

RESUMEN

A taste sensor with lipid/polymer membranes can objectively evaluate taste. As previously reported, caffeine can be detected electrically using lipid/polymer membranes modified with hydroxybenzoic acids (HBAs). However, a systematic understanding of how HBAs contribute to caffeine detection is still lacking. In this study, we used various HBAs such as 2,6-dihydroxybenzoic acid (2,6-DHBA) to modify lipid/polymer membranes, and we detected caffeine using a taste sensor with the modified membranes. The effect of the concentrations of the HBAs on caffeine detection was also discussed. The results of the caffeine detection indicated that the response to caffeine and the reference potential measured in a reference solution were affected by the log P and pKa of HBAs. Furthermore, the taste sensor displayed high sensitivity to caffeine when the reference potential was adjusted to an appropriate range by modification with 2,6-DHBA, where the slope of the change in reference potential with increasing 2,6-DHBA concentration was steep. This is helpful in order to improve the sensitivity of taste sensors to other taste substances, such as theophylline and theobromine, in the future.


Asunto(s)
Cafeína , Gusto , Hidroxibenzoatos , Lípidos , Polímeros , Gusto/fisiología
11.
Plants (Basel) ; 12(1)2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36616133

RESUMEN

Non-anthocyanin compounds (NAN) such as flavonol, flavanol, and phenolic acids should be considered in the characterization of minority red grapevine varieties because these compounds are involved in copigmentation reactions and are potent antioxidants. Sixteen NAN were extracted, identified, and quantified by High Performance Liquid Chromatography (HPLC) from grapes of 28 red genotypes of Vitis vinifera L. grown in Galicia (Northwest of Spain) in 2018 and 2019 vintages. The percentage of total NAN with respect to the total polyphenol content (TPC) values was calculated for each sample and established into three categories: high percentage NAN varieties (NANV), those varieties showing low percentages of NAN (ANV), and finally those varieties showing medium percentages of NAN (NANAV). 'Xafardán' and 'Zamarrica', classified as NANAV, had high values of TPC and showed good percentages of flavonol and flavanol compounds. Principal component analyses (PCA) were performed with flavonol, flavanol, and phenolic acid profiles. The flavonol and flavanol profiles allowed a good discrimination of samples by variety and year, respectively. The flavonol profile should therefore be considered as a potential varietal marker. The results could help in the selection of varieties to be disseminated and in the identification of the most appropriate agronomic and oenological techniques that should be performed on them.

12.
Materials (Basel) ; 16(1)2022 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-36614694

RESUMEN

This study explores the characteristics of electrodeposition of the three hydroxybenzaldehyde isomers and selected hydroxybenzoic acids (4-hydroxybenzoic acid, salicylic acid, 3,5-dihydroxybenzoic acid) from mesityl oxide solvent. Similar to recent advances of this solvent, used by electrochemical studies, the carbon-carbon double bond had significant influence on the formation of polymers from the outlined molecules. In case of most substrates the peak currents increased to a steady-state but electropolymerization of some substrates caused significant deactivation. Scanning electron microscopic and complementary voltammetric studies facilitated that the electrochemically formed polymers are present on the electrode surface in stackings. In viewpoint of analysis of 2-phenylphenol, the modifying deposit formed from 4-hydroxybenzaldehyde was the best with 5 µM detection limit obtained with differential pulse voltammetry. Furthermore, a new procedure was chosen for the involvement of a cavitand derivative into the organic layers with the purpose to improve the layer selectivity (subsequent electrochemical polymerization in an other solution). Further studies showed that in this way the sensitivities of as-modified electrodes were a little worse than without this step, thus indicating that application of this step is disadvantageous. Recovery studies of 2-phenylphenol were carried out on lemon rind without any treatment, and it was compared with the case when the outer yellow layer was removed by rasping. The inner tissues showed very high adsorption affinity towards 2-phenylphenol.

13.
Nutrients ; 13(9)2021 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-34578985

RESUMEN

Seven derivatives of plant-derived hydroxybenzoic acid (HBA)-including 2,3-dihydroxybenzoic (2,3-DHB, pyrocatechuic), 2,4-dihydroxybenzoic (2,4-DHB, ß-resorcylic), 2,5-dihydroxybenzoic (2,5-DHB, gentisic), 2,6-dihydroxybenzoic (2,6-DHB, γ-resorcylic acid), 3,4-dihydroxybenzoic (3,4-DHB, protocatechuic), 3,5-dihydroxybenzoic (3,5-DHB, α-resorcylic), and 3,4,5-trihydroxybenzoic (3,4,5-THB, gallic) acids-were studied for their structural and biological properties. Anti-/pro-oxidant properties were evaluated by using DPPH• (2,2-diphenyl-1-picrylhydrazyl), ABTS•+ (2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), FRAP (ferric-reducing antioxidant power), CUPRAC (cupric-reducing antioxidant power), and Trolox oxidation assays. Lipophilicity was estimated by means of experimental (HPLC) and theoretical methods. The antimicrobial activity against Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa), Staphylococcus aureus (S. aureus), Bacillus subtilis (B. subtilis), Salmonella enteritidis (S. enteritidis), and Candida albicans (C. albicans) was studied. The cytotoxicity of HBAs in MCF-7 and MDA-MB-231 cell lines was estimated. Moreover, the structure of HBAs was studied by means of experimental (FTIR, 1H, and 13C NMR) and quantum chemical DFT methods (the NBO and CHelpG charges, electrostatic potential maps, and electronic parameters based on the energy of HOMO and LUMO orbitals). The aromaticity of HBA was studied based on the calculated geometric and magnetic aromaticity indices (HOMA, Aj, BAC, I6, NICS). The biological activity of hydroxybenzoic acids was discussed in relation to their geometry, the electronic charge distribution in their molecules, their lipophilicity, and their acidity. Principal component analysis (PCA) was used in the statistical analysis of the obtained data and the discussion of the dependency between the structure and activity (SAR: structure-activity relationship) of HBAs. This work provides valuable information on the potential application of hydroxybenzoic acids as bioactive components in dietary supplements, functional foods, or even drugs.


Asunto(s)
Antiinfecciosos/farmacología , Antioxidantes/farmacología , Citotoxinas/farmacología , Hidroxibenzoatos/farmacología , Extractos Vegetales/farmacología , Especies Reactivas de Oxígeno/farmacología , Línea Celular Tumoral/efectos de los fármacos , Humanos , Hidroxibenzoatos/química , Células MCF-7/efectos de los fármacos , Relación Estructura-Actividad
14.
Antioxidants (Basel) ; 10(5)2021 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-33946636

RESUMEN

BACKGROUND: Life expectancy is increasing along with the rising prevalence of cognitive disorders. Among the factors that may contribute to their prevalence, modifiable risk factors such as diet may be of primary importance. Unarguably, plant-based diets rich in bioactive compounds, such as polyphenols, showed their potential in decreasing risk of neurodegenerative disorders. Therefore, the aim of the present study is to investigate whether exposure to components of plant-based diets, namely phenolic acids, may affect cognitive status in older Italian adults. METHODS: The demographic, lifestyle and dietary habits of a sample of individuals living in southern Italy were analyzed. Dietary intake was assessed through food frequency questionnaires (FFQs). Data on the phenolic acids content in foods were estimated using the Phenol-Explorer database. Cognitive status was evaluated using The Short Portable Mental Status Questionnaire. Multivariate logistic regression analyses were used to assess the associations. RESULTS: The mean intake of phenolic acids was 346.6 mg/d. After adjustment for potential confounding factors, individuals in the highest quartile of total phenolic acid intake were less likely to have impaired cognitive status (OR = 0.36 (95% CI: 0.14, 0.92)); similarly, the analysis for subclasses of phenolic acids showed the beneficial effect toward cognitive status of greater intake of hydroxycinnamic acids (OR = 0.35 (95% CI: 0.13, 0.91)). Among individual compounds, only higher intake of caffeic acid was inversely associated with impaired cognitive status (OR = 0.32 (95% CI: 0.11, 0.93)); notably, the association with ferulic acid intake was significant only when adjusting for background characteristics, and not for adherence to the Mediterranean diet. CONCLUSIONS: This study revealed that greater intakes of dietary phenolic acids were significantly inversely associated with impaired cognition, emphasizing the possible role of phenolic acids in the prevention of cognitive disorders.

15.
Antioxidants (Basel) ; 10(3)2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33807526

RESUMEN

Barley (Hordeum vulgare) accumulates phenolic compounds (PhCs), which play a key role in plant defense against environmental stressors as antioxidants or UV screening compounds. The influence of light and atmospheric CO2 concentration ([CO2]) on the accumulation and localization of PhCs in barley leaves was examined for two varieties with different tolerances to oxidative stress. PhC localization was visualized in vivo using fluorescence microscopy. Close relationships were found between fluorescence-determined localization of PhCs in barley leaves and PhC content estimated using liquid chromatography coupled with mass spectroscopy detection. Light intensity had the strongest effect on the accumulation of PhCs, but the total PhC content was similar at elevated [CO2], minimizing the differences between high and low light. PhCs localized preferentially near the surfaces of leaves, but under low light, an increasing allocation of PhCs in deeper mesophyll layers was observed. The PhC profile was significantly different between barley varieties. The relatively tolerant variety accumulated significantly more hydroxycinnamic acids, indicating that these PhCs may play a more prominent role in oxidative stress prevention. Our research presents novel evidence that [CO2] modulates the accumulation of PhCs in barley leaves. Mesophyll cells, rather than epidermal cells, were most responsive to environmental stimuli in terms of PhC accumulation.

16.
J Agric Food Chem ; 69(16): 4816-4826, 2021 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-33855852

RESUMEN

Beer antioxidants originate mainly from malts, classified as colored, caramel, and roasted, according to the malting process. This study aimed to characterize, in terms of phenolic antioxidants, three types of Pale Ale craft beers brewed using increasing percentage of dark malt (0, 5, and 15% Caraamber malt, called PA100, PA95, PA85, respectively) and to evaluate the impact of dealcoholization by osmotic distillation (OD) on the same antioxidants. All the alcoholic (PA, 6.2-6.8 vol %) and low alcoholic (LA-PA, 1 vol %) beers were analyzed by HPLC-ESI-MS/MS, total phenolic content (TPC), and antioxidant activity (AA): similar phenolic profiles were evidenced and 43 compounds identified or tentatively identified. Some differences were found among PA100, PA95, and PA85: PA85 was richer in free phenolic compounds (10.55 mg/L) and had a higher TPC (463.7 GAE mg/L) and AA (852.1 TE mg/L). LA-PA beers showed the same phenolic profile and similar TPC and AA compared to PA beers; however, there were some differences regarding LA-PA85 (5.91 mg/L). Dealcoholization by OD seemed to weakly affect the phenolic fraction. ESI-MS/MS infusion experiments evidenced oligosaccharides, small organic acids, and amino acids, whose presence was confirmed and quantitated by NMR: besides ethanol and other alcohols, weak to strong loss of low-molecular-weight metabolites was evidenced in LA-PA beers.


Asunto(s)
Antioxidantes , Cerveza , Antioxidantes/análisis , Cerveza/análisis , Destilación , Metaboloma , Espectrometría de Masas en Tándem
17.
Food Res Int ; 141: 110149, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33642015

RESUMEN

Human milk (HM) has been proven to have important and essential antioxidant properties to counteract infant susceptibility to oxidative stress. Phenolic compounds are secondary metabolites which come from plants and are potent natural antioxidants. The ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method used in the present study allowed the quantification of 26 phenolic compounds (ten hydroxybenzoic acids, seven hydroxycinnamic acids, four flavonoids, three hydroxybenzaldehydes and two other polyphenols) in HM samples at different stages of lactation (colostrum, transitional milk and mature milk) and infant formulas (IF). Many of the phenolic compounds identified have been reported to be present in HM for the first time. The total phenolic compound content (TPC) was quantified using the Folin assay and the antioxidant activity (AC) was evaluated with the DPPH, ABTS and FRAP assays. Significant differences were evidenced between HM and IF. HM from mothers with an adherence to a Mediterranean diet contained twice as many individual phenolic compounds as infant formulas, with a higher proportion of hydroxybenzoic acids. Conversely, IF showed a higher proportion of hydroxycinnamic acids. Overall, the antioxidant activity of HM showed small variations during lactation.


Asunto(s)
Antioxidantes , Leche Humana , Antioxidantes/análisis , Cromatografía Liquida , Femenino , Humanos , Lactante , Fórmulas Infantiles , Lactancia , Leche Humana/química , Embarazo , Espectrometría de Masas en Tándem
18.
Talanta ; 225: 122061, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33592780

RESUMEN

The luminescent terbium (Tb3+)-loaded supramolecular gels were facilely prepared through the self-assembly of Fmoc-diphenylalanine (FmocPhePhe) at room temperature. Hydroxybenzoic acid (HA, the isomers are denoted as 2-HA, 3-HA, and 4-HA depending upon the positions of hydroxyl groups) was used as a sensitizer to Tb3+. The luminescence sensitization of Tb3+ in the gels was realized by the coordination with hydroxybenzoic acids. The spectra of luminescence, UV-vis, FT-IR, and 1H NMR verified that this sensitization was attributed to the energy transfer from hydroxybenzoic acids to Tb3+. The results of XRD, SEM, and phase transfer temperature further indicated that the initial molecule arrangement of the gels was significantly changed by 2-HA, resulting in more ordered and more compact morphology of the gels. 2-HA exhibited more effective sensitization to Tb3+ in the gels than 3-HA and 4-HA. It was also found that 2-HA did not affect the self-assembly of FmocPhePhe. Due to the effective fluorescence sensitization by 2-HA, the as-prepared gels can be used for salicylic acid sensing with 6.8 µM of the detection limit. This strategy has been successfully used for the detection of salicylates in pharmaceuticals and cosmetics.


Asunto(s)
Luminiscencia , Terbio , Transferencia de Energía , Geles , Espectroscopía Infrarroja por Transformada de Fourier
19.
Antioxidants (Basel) ; 9(12)2020 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-33327632

RESUMEN

Specialized metabolites constitute a major antioxidant system involved in plant defence against environmental constraints, such as tropospheric ozone (O3). The objective of this experiment was to give a thorough description of the effects of an O3 pulse (120 ppb, 5 h) on the phenylpropanoid metabolism of sage, at both biochemical and molecular levels. Variable O3-induced changes were observed over time among the detected phenylpropanoid compounds (mostly identified as phenolic acids and flavonoids), likely because of their extraordinary functional diversity. Furthermore, decreases in the phenylalanine ammonia-lyase (PAL), phenol oxidase (PPO), and rosmarinic acid synthase (RAS) activities were reported during the first hours of treatment, probably due to an O3-induced oxidative damage to proteins. Both PAL and PPO activities were also suppressed at 24 h from the beginning of exposure, whereas enhanced RAS activity occurred at the end of treatment and at the recovery time, suggesting that specific branches of the phenolic pathways were activated. The increased RAS activity was accompanied by the up-regulation of the transcript levels of genes like RAS, tyrosine aminotransferase, and cinnamic acid 4-hydroxylase. In conclusion, sage faced the O3 pulse by regulating the activation of the phenolic biosynthetic route as an integrated defence mechanism.

20.
Food Res Int ; 136: 109298, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32846511

RESUMEN

Phenolic acids are the most prominent group of bioactive compounds present in various plant sources. Hydroxybenzoic acids and hydroxycinnamic acids, the aromatic secondary metabolites imparting typical organoleptic characteristics to food are the major phenolic acids, and they are linked to several health benefits. Fruit and beverage crops being the richer sources of phenolic acids have been studied in depth, but phenolic acids from vegetables are largely overlooked. Though lesser in quantity in many vegetables, there is a need to explore the health benefits of the phenolic acids present in them. In this review, the importance of vegetables as a significant source of phenolic acids is emphasized. Vegetables being easily accessible throughout the year and consumed in larger quantities compared to fruits in our daily diet will probably contribute to significant health benefits. Since vegetables are often processed before consumption, the changes in phenolic acids as influenced by processing methods are highlighted. Best processing methods, pre-treatments and storage conditions for higher retention of phenolic acids have been highlighted to minimize their losses. The phenolic acids in vegetables and their health benefits have been cluster mapped, which may facilitate further research for nutraceutical development for specific health concerns. The processing stability of phenolic acids coupled with higher consumption indicates that they may be a potential source of phenolic acids in the diet. It is expected that the popularization of vegetables as a source of phenolic acids in daily diet will help in ameliorating the adverse effect of some of the lifestyle diseases.


Asunto(s)
Ácidos Cumáricos/análisis , Dieta Saludable , Manipulación de Alimentos/métodos , Hidroxibenzoatos/análisis , Verduras/química , Disponibilidad Biológica , Ácidos Cumáricos/química , Estabilidad de Medicamentos , Almacenamiento de Alimentos/métodos , Humanos , Hidroxibenzoatos/química , Estructura Molecular
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